The control chain can be either a chain which is closed or endless and which engages a chain sprocket on a drive unit, or an open or finite length chain, the end links of which are fastened to the drive unit. In the latter case, it often happens that during the assembly to the vehicle, chain locks have been welded approximately on the side of a suitable housing part of the pivotal drive unit, which side lies opposite the chain sprocket, into which chain locks the control chain was placed. Or radially directed tapped holes were provided in the housing part, into which tapped holes screws were screwed and which were placed through the two bolts of a chain link. The area for mounting the chain locks or the threads results from the respective position of the chain sprocket relative to the drive unit and depends on the type of construction of the vehicle or the arrangement of the drive unit (left or right wheel or only single-wheel drive). The mounting of the fastening elements during the installation makes the installation sequence more difficult, in particular when, for example, the entire drive unit must be exchanged by the operator of the vehicle, and at a location whereat suitable shop equipment often does not exist. Also in particular welding on a finish mounted gearing arrangement requires particular skill and precautions in order to avoid damage to the bearings and/or the gears.
For tensioning or retensioning the control chain, the chain sprocket is supported on a readjustable rocker arm or the like. The structural expense for this is significant.
Therefore, the basic purpose of the present invention is to provide a control chain connection, which can be used independent of the position of the chain sprocket relative to the drive unit, without having to carry out any reworking on the drive unit, and which permits a simple tensioning or retensioning of the chain.
To attain the purpose, a control chain connection utilizes an arrangement of several holes in a cricle, into which a chain holder is mounted and which engages selectively directly or indirectly the chain ends, to facilitate an easy insertion of the drive unit without having to carry out subsequent operations and without having to take into consideration specific vehicle structural conditions. At the same time, the combination with a chain tensioning means makes possible a simplification for the arrangement of the chain sprocket or of the control motor.